2D/3D display switching technology is a trend for 3D display devices. With the 2D/3D display switching technology, a 3D display device can display images in a 2D display mode or a 3D display mode upon a user's request. FIG. 1 and FIG. 2 show a conventional 2D/3D switching device. As shown in FIG. 1, a 2D/3D switching device includes a micro-lens substrate 1 and a flat substrate 2 arranged in parallel. First electrode 3 and second electrode 4 are placed on the surfaces of micro-lens substrate 1 and flat substrate 2, respectively. Further, a liquid crystal layer 5 is positioned between micro-lens substrate 1 and flat substrate 2.
As shown in FIG. 1, when the optical axis of liquid crystal molecules in liquid crystal layer 5 is parallel to flat substrate 2, incident polarized lights have a polarization direction parallel to the direction of the optical axis of the liquid crystal, and the liquid crystal molecules have a refractive index of ne, and ne is not equal to the refractive index of micro-lens substrate 1, np. Thus the incident polarized lights are refracted at the surface of micro-lens substrate 1. Therefore, at this point, the 2D/3D switching device shows a lens effect and can be used to realize 3D display.
As shown in FIG. 2, when the optical axis of liquid crystal molecules is perpendicular to the flat substrate 2, the incident polarized lights have a polarization direction perpendicular to the optical axis of liquid crystal, and the liquid crystal molecules have a refractive index of no, and no is equal to the refractive index of micro-lens substrate 1, np. Thus the incident polarized lights pass directly through micro-lens substrate 1 without refraction. Therefore, at this point, the 2D/3D switching device does not show a lens effect and can be used to realize 2D display.
Further, rotation of the long axis of liquid crystal molecules is controlled by applying driving voltages on first electrode 3 and second electrode 4 to create an electric field. The driving voltages to first electrode 3 and second electrode 4 are respectively provided by two separate voltage output modules (not shown). In conventional 2D/3D switching devices, the driving voltage provided by the voltage output module for each of the first electrode and second electrode is fixed. When the driving voltage provided by one voltage output module shifts due to design errors or other reasons, the other voltage output module cannot adjust its driving voltage accordingly, which could lead to incorrect switching behavior. In addition, because the voltage output modules can only provide fixed voltages, 3D display areas are also fixed and the user cannot change locations of the 3D display areas. Further, in the conventional 2D/3D switching devices, the liquid crystal molecules can only have two rotations angles, one for liquid crystal molecules corresponding to 2D display areas and the other for 3D display areas. Thus, when displaying different 3D contents, same 3D effect may appear, resulting in grainy images.
The disclosed methods and systems are directed to solve one or more problems set forth above and other problems.